Radial club hand is a congenital condition that affects:

Radial club hand is a congenital condition that affects the development of the radius bone in the forearm. This condition can cause the hand to be bent inwards towards the thumb side of the forearm. It can also lead to other abnormalities such as shortening of the arm, stiffness and limited movement in the wrist and elbow, and underdevelopment or absence of the thumb. The severity of radial club hand can vary greatly among individuals. Some people may have minor deformities that do not affect function, while others may have significant physical disabilities. The exact cause of radial club hand is unknown, but it is thought to occur during the first trimester of pregnancy. Treatment typically involves physical therapy and, in more severe cases, surgery to correct the deformity.